JP2000202873A - Mold releasing method in molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold releasing method capable of reducing the interval between a fixed mold and a second movable mold in the mold opened state of a molding machine. SOLUTION: An injection molding machine 2 is equipped with a fixed mold 4, the first movable mold 6 opposed thereto, the second movable mold 9 opposed to the first movable one 6, the first cavity 22 provided between the fixed mold 4 and the first movable mold 6 and the second cavity 24 provided between the first and second movable molds 6, 9. In such a state that the space between the first and second movable molds 6, 9 is closed, both molds are moved to open the space between the first movable mold 6 (shown by a solid line) and the fixed mold 4 to perform the work for taking out the product molded by the first cavity 22. Subsequently, the first movable mold 6 is moved to close the space between the fixed mold 4 and the first movable mold 6 while the space between the first movable mold 6 (shown by a chain line) and the second movable mold 9 is opened to perform the work for taking out the product molded by the second cavity 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding apparatus, in particular, a fixed mold, a first movable mold opposed to the fixed mold, and a first movable mold.
A second movable mold facing the movable mold, the fixed mold and the first movable mold;
At least one first cavity for molding a product provided between both mating surfaces of the movable mold, and at least one second cavity for molding a product provided between both mating surfaces of the first movable mold and the second movable mold; And a mold release method in a molding apparatus provided with:

[0002]

2. Description of the Related Art Hitherto, in this type of molding apparatus, means for simultaneously opening the fixed mold and the first movable mold and the first and second movable molds when releasing the mold has been adopted.

[0003]

However, when the above-mentioned means is employed, the space between the fixed mold and the second movable mold in the mold open state becomes large, and the occupancy of the molding apparatus in the factory space becomes high. , Etc.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for releasing a mold in which the distance between the fixed mold and the second movable mold in the mold open state can be made smaller than that of the conventional mold. .

[0005] To achieve the above object, according to the present invention,
A fixed mold, a first movable mold opposed to the fixed mold, a second movable mold opposed to the first movable mold, and at least one provided between both mating surfaces of the fixed mold and the first movable mold. A first cavity for molding a product, the first movable die and the second
A mold release method in a molding apparatus having at least one second cavity for molding a product provided between both mating surfaces of a movable mold, wherein after the molding operation, the first movable mold and the second movable mold are separated.
The movable mold is moved in a state in which the movable mold is closed between the two molds, thereby opening the space between the fixed mold and the first movable mold so as to open the first mold.
Take out the product molded by the cavity,
Next, the first movable mold is moved to close the fixed mold and the first movable mold, and the first movable mold and the second movable mold are closed.
There is provided a mold release method in a molding apparatus, in which a gap between movable dies is opened to take out a product molded by the second cavity.

[0006] When the two products are taken out by opening the molds in the order described above, it is difficult to open the space between the fixed mold and the first movable mold and between the first and the second movable molds at the same time as in the related art. In comparison, the space between the fixed mold and the second movable mold in the mold open state is reduced, and thereby the space in the factory can be effectively used. This is remarkable, for example, when the product has a deep bowl shape, that is, when the product has a long length in the mold opening and closing direction.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A deep bowl-shaped product 1 shown in FIGS. 1 and 2 is obtained by injection molding using a molding material made of a synthetic resin, for example, PP, PE, ABS or the like.

As shown in FIGS. 3 and 4, an injection molding apparatus 2 as a molding apparatus includes a stationary mold 4 having a vertical mating surface 3,
One vertical mating surface 5 is attached to the vertical mating surface 3 of the fixed mold 4.
And the first movable mold 6 that can reciprocate in the horizontal direction
And a second reciprocating horizontal reciprocating member 8 in which the vertical mating surface 8 is opposed to the other vertical mating surface 7 of the first movable die 6.
And a movable mold 9.

The fixed die 4 is mounted on a fixed substrate 10, and the second movable die 9 is mounted on a movable substrate 11 facing the fixed substrate 10. The movable substrate 11 is slidably supported by upper and lower two guide rods 12 and, therefore, four horizontal guide rods 12.
The guide rods 12 are provided between one fixed substrate 10 and the other fixed substrate (not shown). Movable substrate 1
1 is connected to a piston rod 14 of a double-acting main working cylinder 13, and the main working cylinder 13 is horizontally supported by another fixed substrate (not shown).

The first movable die 6 has a sliding plate 15 integrally at its lower end, and downward gutter-like portions 16 on both sides of the sliding plate 15 are provided on two lower guide rods 12. Are slidably mounted respectively. In addition, four guide pins 17 are provided so as to protrude from the mating surface 8 of the second movable die 9, and are slidably inserted into four guide holes 18 of the first movable die 6. Further, on both sides of the second movable die 9, the single-acting sub-acting cylinders 19
Are mounted in parallel with the respective guide pins 17, and the piston rods 20 of the respective sub-actuation cylinders 19 are connected to the protruding plates 21 existing on the respective side surfaces of the first movable die 6.

In FIG. 3, the second movable mold 9 is located at a mold opening position which is a retreat limit with respect to the fixed mold 4. When closing the mold,
As shown in FIG. 5, the operation of the two sub-actuating cylinders 19 causes the first movable mold 6 to move forward to match the fixed mold 4, and then the operation circuits of the respective sub-acting cylinders 19 are opened. The second movable die 9 is moved forward by the operation of the first movable die 6 so as to match the first movable die 6, and the main working cylinder 13
The three dies 4, 6, and 9 are held in a clamped state by the pressing force.

In this clamped state, as shown in FIG. 6, between the mating surfaces 3 and 5 of the fixed mold 4 and the first movable mold 6,
At least one, in the illustrated example, one first cavity 22 for product molding and a first supply path 23 for molding material communicating with the first cavity 22 are formed. In addition, at least one, in the illustrated example, one product forming second cavity 24 is provided between both mating surfaces 7 and 8 of the first movable die 6 and the second movable die 9.
And a second molding material communicating with the second cavity 24.
A supply path 25 is formed.

Further, a sprue 26 is formed on the fixed mold 4,
The entrance 27 of the sprue 26 is
Opening on the mounting surface 29 of the fixed mold 4 so as to face
The outlet 30 communicates with the first supply path 23. Injection cylinder 3
1 is disposed and fixed on the fixed mold 4 side, and its nozzle 32
Are accommodated in the hole 28 and communicate with the entrance 27 of the sprue 26. In the sprue 26, the space between the inlet and outlet 27, 30 is heated by a heater 33 as a heating means provided in the fixed mold 4 in order to keep the molding material in a molten state. The outlet 30 is formed in a tapered hole whose inner diameter increases from the inside of the fixed mold 4 toward the first supply path 23.

The first and second supply paths 23 and 25 are communicated by a communication path 34 provided in the first movable die 6.
In the communication passage 34, a portion between an inlet 35 communicating with the first supply passage 23 and an outlet 36 communicating with the second supply passage 25 serves as a heating means provided on the first movable die 6 so as to keep the molding material in a molten state. Is heated by the heater 37. The inlet 35 is formed as a small-diameter equal-diameter hole, while the outlet 36 is disposed at a higher position than the inlet 35 and has a tapered hole whose inside diameter increases from the inside of the first movable die 6 toward the second supply passage 25. Formed.

The first movable mold 6 is provided with a valve device 38 for opening and closing the inlet 35. The valve device 38 includes a pin-shaped valve body 39 inserted into and removed from the inlet 35, and a double-acting small operation cylinder 40 as an operation source for reciprocating the pin-shaped valve body 39. A support hole 41 coaxial with the inlet 35 is formed in the first movable die 6, and a pin-shaped valve body 39 is formed in the support hole 41.
Are slidably fitted. The small working cylinder 40 is provided so as to protrude from the mating surface 7 on the side of the second movable mold 9 of the first movable mold 6.
Is provided with a recess 42 in which a small working cylinder 40 can be accommodated. As a result, the valve device 38 is housed in the first and second movable dies 6 and 9 in a closed state.

As shown in FIG. 7, the communication passage 34 has a relatively large cylindrical space 43 near the entrance 35, and a circular valve body support plate 44 is fitted in the space 43. The valve body support plate 44 has a support hole 45 slidably penetrating the tip end side of the pin-shaped valve body 39, and at least one, four in the illustrated example, formed on the outer periphery of the support hole 45. And a circulation hole 46. This valve body support plate 44 can prevent the pin-shaped valve body 39 from bending due to the flow of the molten molding material from the sprue 26.

As described above, when the first movable die 6 is provided with the communication passage 34 that communicates between the first and second supply passages 23 and 24, the injection cylinder 31 is disposed and fixed on the fixed die 4 side. It becomes possible. Thus, the weight of the first movable mold 6 can be reduced, the wear of the sliding plate 15 can be reduced, and the structure of the mold 6 can be simplified.

In injection molding of the product 1, a molten molding material made of PP is injected into the sprue 26 from the nozzle 32 of the injection cylinder 31 in the mold clamping state shown in FIGS. Into the first cavity 22 through the first supply path 23, the communication path 34, and the second supply path 25 into the second cavity 24, respectively.
Is molded.

In releasing the mold, as shown in FIGS. 8 and 9, the small working cylinder 40 is operated to close the inlet 35 of the communication passage 34 by the pin-shaped valve body 39, and the auxiliary working cylinder 1
9 and the main operating cylinder 13
Is operated to retract the first movable mold 6 and the second movable mold 9 in a state in which the molds 6 and 9 are closed, thereby opening the space between the fixed mold 4 and the first movable mold 6 so as to open the first movable mold 6 and the first movable mold 6. The product 1 molded by the cavity 22 is taken out.

The outlet 30 of the sprue 26 and the first supply path 2
Since 3 is a non-heating area, the molten molding material in them is hardened to become a scrap portion 47, and the scrap portion 47 is separated from the outlet 30 and the first supply path 23 together with the product 1. Further, when the molten molding material m present in the heating area of the sprue 26 slightly protrudes to the outlet 30, it becomes a tapered hole, and the inner peripheral surface thereof, that is, the area of the cooling surface in contact with the molten molding material m is expanded, In addition, since it is a non-heating area, the protruding portion immediately becomes high in viscosity and serves as a plug, thereby preventing the molten molding material m from leaking from the outlet 30 of the sprue 26. In the communication passage 34,
Since the inlet 35 is closed by the pin-shaped valve body 39, leakage of the molten molding material m from the inlet 35 is also prevented.

Next, as shown in FIGS. 10 and 11, both sub-actuating cylinders 19 are respectively operated to advance the first movable mold 6 to close the space between the fixed mold 4 and the first movable mold 6. Then, the space between the second movable molds 9 is opened to take out the product 1 molded by the second cavity 24.

Outlet 36 of communication path 34 and second supply path 2
Since 5 is a non-heating area, the molten molding material in them is hardened to become a scrap portion 47, and the scrap portion 47 is separated from the outlet 36 and the second supply passage 25 together with the product 1. Also, when the molten molding material m in the heating area of the communication passage 34 slightly projects to the outlet 36, similarly to the above, the molten molding material m is a tapered hole, and its inner peripheral surface, that is, the area of the cooling surface in contact with the molten molding material m. Because of the expansion and the non-heating area, the protruding portion immediately becomes highly viscous and serves as a plug, thereby preventing the molten molding material m from leaking from the outlet 36 of the communication passage 34. The communication path 34
Is closed by the pin-shaped valve element 39, so that the molten molding material m does not leak.

When the two products 1 are taken out by opening the molds in the order described above, the space between the fixed mold 4 and the first movable mold 6 and the space between the first and second movable molds 6 and 9 are simultaneously opened. As compared with the case, the space between the fixed mold 4 and the second movable mold 9 in the mold open state is made smaller, whereby the space in the factory can be effectively used. This is remarkable when the product 1 has a deep bowl shape as in the embodiment, that is, when the length of the product 1 in the mold opening and closing direction is long.

At the start of the second or subsequent injection molding, FIG.
As shown in the figure, the inlet 35 of the communication passage 24 is connected to the pin-shaped valve body 39.
, And the closed state is changed as shown in FIG.
The lower part of the supply channel 23 is filled and held until its surface exceeds the inlet 35. When such a method is adopted, FIG.
At the outlet 30 of the sprue 26 and the first supply path 23
It is possible to avoid such a problem that the air in the inside enters the communication path 34 together with the molten molding material m from the sprue 26 to generate a defective product.

[0025]

According to the present invention, by employing the above-described means, the distance between the fixed mold and the second movable mold in the mold opening state is reduced, thereby effectively utilizing the space in the factory. It is possible to provide a mold release method in a molding apparatus that can be achieved. This is remarkable, for example, when the product has a deep bowl shape, that is, when the product has a long length in the mold opening and closing direction.

[Brief description of the drawings]

FIG. 1 is a perspective view of a product.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a side view of the injection molding apparatus with a part broken.

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3;

FIG. 5 is a side view showing a closed state of the injection molding apparatus.

FIG. 6 is an enlarged sectional view of a main part corresponding to FIG. 5;

FIG. 7 is a sectional view taken along line 7-7 of FIG. 6;

FIG. 8 is a side view showing a state in which the fixed mold and the first movable mold are opened in the injection molding apparatus.

FIG. 9 is an enlarged sectional view of a main part corresponding to FIG.

FIG. 10 is a side view showing a state in which the space between the fixed mold and the first movable mold is closed and the space between the first and second movable molds is opened in the injection molding apparatus.

FIG. 11 is an enlarged sectional view of a main part corresponding to FIG.

FIG. 12 is an enlarged sectional view of a main part of the injection molding apparatus at the start of the second and subsequent injection moldings.

[Explanation of symbols]

 Reference Signs List 1 product 2 injection molding device (molding device) 4 fixed die 6 first movable die 9 second movable die 22 first cavity 24 second cavity

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Mitsuya Murata 1-10-1 Shinsayama, Sayama City, Saitama Prefecture Honda Engineering Co., Ltd. F term (reference) 4F202 AA11 AH52 CA11 CB01 CK02 CK06 CK35 CK42 CK84 CK89 CL07 CL09 CM08 CM12 4F206 AA11 AH52 JA07 JQ81 JT06

Claims (1)

[Claims] 1. A fixed mold (4), a first movable mold (6) opposed to the fixed mold (4), and a second movable mold (9) opposed to the first movable mold (6). At least one product molding first cavity (22) provided between both mating surfaces (3, 5) of the fixed mold (4) and the first movable mold (6);
A molding apparatus (2) including at least one product molding second cavity (24) provided between both mating surfaces (7, 8) of the first movable mold (6) and the second movable mold (9). ), Wherein after the molding operation, the first movable die (6) and the second movable die (9)
9) The space between the fixed mold (4) and the first movable mold (6) is opened by moving the mold in a closed state to take out the product (1) molded by the first cavity (22). Next, the first movable mold (6) is moved to close the space between the fixed mold (4) and the first movable mold (6), and between the first movable mold (6) and the second movable mold (9). And releasing the molded product (1) by the second cavity (24).